The capsule endoscope swallowed from the mouth into the digestive system can capture the images of important gastrointestinal tract regions. It can compensate for the blind spot of traditional endoscopic techniques. It enables inspection of the digestive system without discomfort or need for sedation. However, currently available clinical capsule endoscope has some limitations such as the diagnostic information being not able to correspond to the orientation in the body, since the doctor is unable to control the capsule motion and orientation. To solve the problem, it is significant to track the position and orientation of the capsule in the human body. This study presents an AC excitation wireless tracking method in the capsule endoscope, and the sensor embedded in the capsule can measure the magnetic field generated by excitation coil. And then the position and orientation of the capsule can be obtained by solving a magnetic field inverse problem. Since the magnetic field decays with distance dramatically, the dynamic range of the received signal spans three orders of magnitude, we designed an adjustable alternating magnetic field generating device. The device can adjust the strength of the alternating magnetic field automatically through the feedback signal from the sensor. The prototype experiment showed that the adjustable magnetic field generating device was feasible. It could realize the automatic adjustment of the magnetic field strength successfully, and improve the tracking accuracy.
Capsule Endoscopes ; Endoscopy ; Gastrointestinal Tract ; Humans ; Magnetic Fields

Objective To preliminarily evaluate the safety and efficacy of percutaneous vertebroplasty (PVP) with 131I-loaded bone cement in treating vertebral tumor in rabbit models. Methods Twelve New Zealand white rabbits with lumbar vertebral tumor, which was established by puncturing transplant of VX2 carcinoma, were randomly and equally divided into the study group and the control group with 6 rabbits in each group. PVP with injection of 131I-loaded bone cement was carried out in the rabbits of the study group, while PVP with injection of pure bone cement was employed in the rabbits of the control group. The blood cell count was determined in all the animals one day before PVP as well as on the 4th day after PVP. PET-CT examination was performed one day before PVP as well as on the 4th day after PVP to check the stand uptake value (SUV) of each vertebral tumor. SPECT was performed in all rabbits of the study group at one, 4 and 8 days after PVP respectively to estimate the distribution of 131I in the animals’ bodies. Eight days after PVP, blood cell counts, which were determined both before and after PVP, existed between the study group and the control group. SPECT that was performed after PVP indicated that 131I was mainly accumulated within PVP-treated vertebrae, and the distribution of 131I showed no obvious changes at different points of time after the procedure. Before PVP, the difference in SUV between the two groups was of no statistical significance (F = 0.765, P > 0.05). In the study group, the postoperative SUV was significantly lower than the preoperative SUV (F = 423.792, P < 0.05). Pathological examination showed that the extent of tumor cell necrosis around the bone cement in the study group was remarkably bigger than that in the control group. Conclusion In treating vertebral tumors with PVP, the use of 131I-loaded bone cement is clinically feasible, and short-term follow-up indicates that this technique is safe and effective.

China ; Disaster Medicine ; Disasters ; statistics & numerical data ; Earthquakes ; statistics & numerical data ; First Aid ; statistics & numerical data ; Humans ; Mass Casualty Incidents ; statistics & numerical data ; Rescue Work

Adolescent ; Adult ; Female ; Femoral Fractures ; diagnostic imaging ; surgery ; Fracture Fixation, Internal ; methods ; Humans ; Knee Injuries ; diagnostic imaging ; surgery ; Male ; Middle Aged ; Radiography ; Tibial Fractures ; diagnostic imaging ; surgery

AIM:To explore the changes and significance of Kupffer cells in the process of tree shrew chroni -cally infected with hepatitis B virus (HBV).METHODS:The animals were divided into 3 groups.Group A consists of 6 tree shrews that were identified as persistently infected with HBV;group B consists of 3 tree shrews that were suspected as persistently infected with HBV;group C consists of 4 tree shrews that were not inoculated with HBV and were applied as normal controls.Liver biopsies were collected regularly from all animals , and the Kupffer cells were isolated , purified and primarily cultured.The techniques of flow cytometry , immunohistochemistry, lysosomal fluorescent probe staining and real-time RT-PCR were applied to determine the number and function of these Kupffer cells .RESULTS: The result showed that the count and proportion of CD 163+cells in group A were significantly higher than those in group B and group C ( P<0.05).Meanwhile, the fluorescence intensity levels of lysosomal , the number of lysozyme-positive cells and the mRNA ex-pression level of TNF-αin the Kupffer cells in group A were significantly lower than those in group B and group C ( P<0.05).CONCLUSION:Kupffer cells may play a regulatory role during host’s chronic HBV infection.

Objective To compare the effects of preserving the posterior ligament complex (PLC) with torque loading and displacement loading on the biomechanical properties of the adjacent segments after lumbar decompression and fusion. Methods Six fresh male cadaver lumbar specimens of T12-S2 were tested in the sequence of intact, L4-5 laminotomy (preserving the PLC) with fixation and L4-5 laminectomy (destructing the PLC) with fixation, by applying both displacement loading and torque loading, respectively. Ranges-of-motions (ROMs) of the adjacent segments were measured under a noncontact photographic recording system. Results In displacement-loading mode, the flexion ROM in laminectomy group was significantly higher than that in laminotomy group, and no obvious ROM differences were found in the laminectomy and laminotomy groups under extension, lateral bending, and rotation movement. Conclusions Torque loading and displacement loading have different biomechanical effects on the adjacent segments after lumbar decompression and fusion. Compared with the laminotomy method, in which the PLC is preserved, the laminectomy method in which PLC structures are damaged can obviously lead to an increment of flexion ROMs at the adjacent segments, and also increase the ROMs of the adjacent segments under extension, lateral bending, and rotation movements, which might increase the risk of further instability of the fused adjacent segments.

Novel uniform-sized magnetic molecularly imprinted polymers (MMIPs) were synthesized for selective recognition of active antitumor ingredients of kaempferol (KMF) and protoapigenone (PA) in Macrothelypteris torresiana (M. torresiana) by surface molecular imprinting technique in this study. Super paramagnetic core-shell nanoparticles (γ-MPS-SiO2@Fe3O4) were used as seeds, KMF as template molecule, acrylamide (AM) as functional monomer, and N, N'-methylene bisacrylamide (BisAM) as cross-linker. The prepared MMIPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), transmission electron microscopy (TEM) and thermo-gravimetric analysis (TGA), respectively. The recognition capacity of MMIPs was 2.436 times of non-imprinted polymers. The adsorption results based on kinetics and isotherm analysis were in accordance with the pseudo-second-order model (R (2)=0.9980) and the Langmuir adsorption model (R (2)=0.9944). The value of E (6.742 kJ/mol) calculated from the Dubinin-Radushkevich isotherm model suggested that the physical adsorption via hydrogen-bonding might be predominant. The Scatchard plot showed a single line (R (2)=0.9172) and demonstrated the homogeneous recognition sites on MMIPs for KMF. The magnetic solid phase extraction (MSPE) based on MMIPs as sorbent was established for fast and selective enrichment of KMF and its structural analogue PA from the crude extract of M. torresiana and then KMF and PA were detected by HPLC-UV. The established method showed good performance and satisfactory results for real sample analysis. It also showed the feasibility of MMIPs for selective recognition of active structural analogues from complex herbal extracts.
Acrylic Resins ; chemical synthesis ; chemistry ; Antineoplastic Agents, Phytogenic ; chemistry ; isolation & purification ; Cyclohexanones ; chemistry ; isolation & purification ; Ferns ; chemistry ; Flavones ; chemistry ; isolation & purification ; Kaempferols ; chemistry ; isolation & purification ; Nanoparticles ; chemistry

OBJECTIVETo determine the methods for establishing an in vivo model of long-term hepatitis B virus (HBV) infection in the Chinese tree shrew (Tupaia belangeri chinensis).

METHODSSeventy-seven neonate (1-3 days old) and 49 young adult (2 weeks to 1 year old) tree shrews were inoculated with different HBV sources (chronic hepatitis B (CHB) human patient serum, single or pooled; HBV-infected tree shrew serum, single only; HBV-infected HepG2.2.15 cells' culture medium supernatant; HBV genome-transfected HepG2.2.15 cells' culture medium supernatant) through various routes of injection (subcutaneous, intraperitoneal, and direct liver via abdominal skin; adults also received intravenous and indirect liver via spleen). Serum and liver biopsies were collected from the animals at various time points post-inoculation for detection of HBV markers by fluorescence quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, time-resolved immunofluorescence, Southern blotting, dot blotting, immunohistochemistry, and microscopy.

RESULTSAmong the neonatal group of tree shrews, six (7.8%) were confirmed as HBV-infected for more than 72 (up to 228) weeks after inoculation and another seven (9.1%) were suspected of persistent infections. None of the young adult tree shrews developed persistent infection. Inoculation with single-source serum from either CHB humans or tree shrews were responsible for the most cases of infections, and the subcutaneous injection produced more infections than the other inoculation routes. The most reliable methods of determining HBV infection status were detection of serum HBV immunoreactive markers and intrahepatic HBV DNA.

CONCLUSIONIn order to establish an in vivo model of CHB in the tree shrew, the animals should be inoculated in the neonatal period using subcutaneous injection.

Animals ; Disease Models, Animal ; Female ; Hep G2 Cells ; Hepatitis B virus ; Hepatitis B, Chronic ; virology ; Humans ; Male ; Tupaia

OBJECTIVETo evaluate the periodontal conditions after the wedge-shaped defect was restored by gingival retraction technique.

METHODSA total of 138 mandibular premolars with wedge-shaped defect were selected and divided into A, B groups. Group A was restored with Dyract after using retraction cord. Group B was directly restored with Dyract. Clinical parameters including plaque index (PLI), gingival index (GI), sulcus bleeding index (SBI), probing depth (PD), volumes of gingival crevicular fluid (GCF) and levels of aspartate aminotransferases (AST) of gingival crevicular fluid were measured at baseline, 1 week, 1 month, 3 months and 6 months after operation.

RESULTSThere was no difference in PLI, GI, SBI, PD between group A and B during 6 months after operation, while the difference of GCF and AST was significant between group A and B at 3 months and 6 months after operation (P < 0.05, P < 0.01).

CONCLUSIONSGingival retraction technique applied in wedge-shaped defect restoration can reduce the damage to the periodontal tissue.

Adolescent ; Adult ; Aspartate Aminotransferases ; analysis ; Dental Plaque Index ; Dental Restoration, Permanent ; methods ; Female ; Gingival Crevicular Fluid ; enzymology ; Humans ; Male ; Periodontal Index ; Young Adult

OBJECTIVETo study the association between serum-specific immunoglobulin E (sIgE) allergens and asthma in children.

METHODSThe serum sIgE allergens were determined using Western blot in 2239 children aged 1-14 years, consisting of 1415 children with asthma alone and 824 children with non-allergic diseases between December 2004 and April 2013. The case-control models of asthma alone and non-allergic diseases were established. The association between allergens and asthma was investigated using multivariate logistic regression analysis.

RESULTSIn the 2239 children, 1028 children (45.91%) were serum sIgE-positive, and the allergen with the highest positive rate was house-dust mite (15.68%), followed by house dust (14.29%) and moulds (13.40%). The results of the case-control analysis showed that house-dust mite, moulds, house dust, and cashew nut/peanut/soybean were significantly associated with the development of asthma. House dust was associated with the development of asthma in the 1-2 years old group (P<0.05). House dust and house-dust mite as allergens were identified as the risk factors for the development of asthma in the 3-14 years old group (P<0.05). In the 6-14 years old group, moulds as allergens were identified as the risk factors for the development of asthma (P<0.05). House dust and house-dust mite as allergens increased the risk of asthma in boys and girls, while moulds and cashew nuts/peanuts/soybeans as allergens increased the risk of asthma in boys.

CONCLUSIONSHouse-dust mite, house dust, and moulds are the most common allergens in children with asthma, and they are closely associated with the development of asthma.

Adolescent ; Age Factors ; Allergens ; blood ; Animals ; Asthma ; blood ; etiology ; Case-Control Studies ; Child ; Child, Preschool ; Dust ; Female ; Humans ; Infant ; Male ; Pyroglyphidae